BATS. 107 



before, with respect to the invariable early retreat of 

 the hirundo apus, or swift, so many weeks before its 

 congeners ; and that not only with us, but also in 

 Andalusia, where they begin to retire about the be- 

 ginning of August. 



The great large bat * (which, by the by, is at pre- 

 sent a non-descript in England, and what I have 

 never been able yet to procure) retires or migrates 

 very early in the summer : it also ranges very high 

 for its food, feeding in a different region of the air ; 

 and that is the reason I never could procure one.f 

 Now, this is exactly the case with the swifts ; for 

 they take their food in a more exalted region than 

 the other species, and are very seldom seen hawking 

 for flies near the ground, or over the surface of the 

 water. From hence I would conclude, that these 

 Urundines, and the larger bats, are supported by some 

 sorts of high-flying gnats, scarabs, or phal&na, that 

 are of short continuance ; and that the short stay of 

 these strangers is regulated by the defect of their 

 food. 



By my journal it appears, that curlews clamoured 

 on to October the thirty-first ; since which, I have 

 not seen or heard any. Swallows were observed on 

 to November the third. 



* The little bat appears almost every month in the year ; 

 but I have never seen the large ones till the end of April, nor 

 after July. They are most common in June, but never in any 

 plenty : are a rare species with us. 



f Mr. White has the merit of first noticing this species in 

 England : it is the vespertilio noctula of Dr. Fleming, and said 

 by that naturalist to winter in Italy. W. J. 



